Stable isotope analysis of the karst hydrological systems in the Bay of Kvarner (Croatia)

Here we present the results of the first systematic analysis of the stable isotope composition of the karst hydrological systems in the Bay of Kvarner. Gaussian mixture modelling, time series analysis and autoregressive integrated moving average (ARIMA) modelling were applied using the stable isotope compositions of the karst groundwater. This study revealed that the recharge is dominated by winter precipitation, the dual-porosity system is dominated by baseflow, the hinterlands of the individual springs have different degrees of karstification and the springs within the Rječina River catchment have higher recharge elevations than the springs in the Bakar Bay catchment.